dsh-tool-lsp
English | 中文
An LSP tool surface for DeepSeek Harness: real
language-server diagnostics, formatting, rename, code actions and symbol navigation,
exposed as five tools the model can call directly.
Tools
| Tool | What it does | Writes to disk |
|---|
lsp_diagnostics | File diagnostics, merging the pull and push channels | no |
lsp_format | Whole-file or range formatting | yes |
lsp_rename | Semantic rename, across files when the server says so | yes |
lsp_code_action | Fixes the language server is willing to apply | yes (when an action is applied) |
lsp_symbols | Document outline / workspace symbol search | no |
Writes go through the Harness filesystem observation policy: a file changed by someone
else since this call read it fails with LSP_WRITE_CONFLICT rather than being
silently overwritten.
Install
dsh plugin --profile web add dsh-tool-lsp
Enable it from dshmarket. The plugin is off by default — click the switch when you
want it, and it takes effect immediately with no restart. The enabled state does not
survive a restart.
Configuration
The language-server table lives in the user profile's patch layer
($DSH_HOME/profiles/<name>/cordis.patch.yml), never in the plugin package: the
package's own cordis.patch.yml has to stay plain insert rows, or dshmarket cannot
hot-mount or hot-unmount this plugin.
- id: lsp
config:
servers:
vtsls:
command: vtsls
args: ["--stdio"]
extensionToLanguage:
".ts": typescript
".tsx": typescriptreact
".js": javascript
".jsx": javascriptreact
projectMarkers: ["package.json", "tsconfig.json"]
configuration: # the answer to workspace/configuration
typescript:
preferences:
includePackageJsonAutoImports: "on"
rust:
command: rust-analyzer
extensionToLanguage:
".rs": rust
projectMarkers: ["Cargo.toml"]
biome:
command: biome
args: ["lsp-proxy"]
extensionToLanguage:
".json": json
".css": css
projectMarkers: ["biome.json"]
# The switch needs its own row: same-id rows merge key by key, and folding them
# into one row breaks the market's toggle
- id: lsp
disabled: true
Server entry fields
| Field | Required | Default | Meaning |
|---|
command | ✅ | — | Executable name, resolved on PATH at mount; a typo fails there, not on first call |
extensionToLanguage | ✅ | — | Extension → LSP language id |
fileGlobs | | [] | Path globs, highest routing priority |
projectMarkers | | [] | Project file names, used to split one extension across servers |
args | | [] | Launch arguments |
env | | {} | Extra environment entries |
initializationOptions | | null | initializationOptions sent with initialize |
configuration | | null | Answer to workspace/configuration, resolved per requested section |
formattingOptions | | null | Overrides the global formatting options (tabSize / insertSpaces) |
Routing
Matched in order, first hit wins:
fileGlobsprojectMarkers — the marker file in the file's nearest ancestor; only chooses among
entries that already map the extensionextensionToLanguage — first match in configuration order
Top-level options
maxDiagnostics (200), maxSymbols (100), maxCodeActions (50), maxResultChars
(16000), maxDiffLines (60), maxDocumentBytes (8 MiB), timeoutMs (60000).
Positions
Tool arguments take 1-based UTF-16 line / character, matching editors. The
0-based wire form and the utf-8 / utf-32 encodings some servers negotiate are
converted internally — the model never has to think about it.
Requirements
The language servers themselves must be on PATH; this plugin does not install them.
vtsls, biome, rust-analyzer, ty, ruff, or any other LSP server.
Known limitations
biome and ruff do not implement textDocument/documentSymbol, so lsp_symbols
returns LSP_UNSUPPORTED for them. They serve diagnostics and formatting only.- A cold server (
rust-analyzer is the usual example) may answer a first diagnostic
pull with nothing at all while it indexes. The plugin retries with backoff and, once
out of attempts, reports what it has.
Development
npm test # 121 unit tests, including protocol coverage over a fake server
npm run verify:servers # every server configured in the patch layer, over real requests
verify:servers reads the servers: table out of the profile patch, starts each real
server, and issues one request per advertised capability. Usage:
node test/verify-servers.mjs [profileDir].
Restart the process after changing plugin source. The market switch changes whether
the plugin is mounted, immediately — but it does not load new code from disk into a
running process (ESM module cache, confirmed by measurement).
License
MIT
